Abstract
The complexes PtRu5(CO)15(PMe2Ph)(μ6-C) (2), PtRu5(CO)14(PMe2Ph)2 (μ6-C) (3), PtRu5(CO)15(PMe3)(μ6-C) (4), PtRu5(CO)14(PMe3)2 (μ6-C) (5), and PtRu5(CO)15(Me2S)(μ6-C) (6) were obtained from the reactions of PtRu5(CO)16(μ6-C) (1) with the appropriate ligand. As determined by NMR spectroscopy, all the new complexes exist in solution as a mixture of isomers. Compounds 2, 3, and 6 were characterized crystallographically. In all three compounds, the six metal atoms are arranged in an octahedral geometry, with a carbido carbon atom in the center. The PMe2Ph and Me2S ligands are coordinated to the Pt atom in 2 and 6, respectively. In 3, the two PMe2Ph ligands are coordinated to Ru atoms. In solution, all the new compounds undergo dynamical intramolecular isomerization by shifting the PMe2Ph or Me2S ligand back and forth between the Pt and Ru atoms. For compound 2, ΔH‡ = 15.1(3) kcal/mol, ΔS‡ = -7.7(9) cal/(mol·K), and ΔG298 = 17.4(6) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 4, ΔH‡ = 14.0(1) kcal/mol, ΔS‡ = -10.7(4) cal/(mol·K), and ΔG298 = 17.2(2) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 6, ΔH‡ = 18(1) kcal/mol, ΔS‡ = 21(5) cal/(mol·K) and ΔG298 = 12(2) kcal/mol. The shifts of the Me2S ligand in 6 are significantly more facile than the shifts for the phosphine ligand in compounds 2-5. This is attributed to a more stable ligand-bridged intermediate for the isomerizations of 6 than that for compounds 2-5. The intermediate for the isomerization of 6 involves a bridging Me2S ligand that can use two lone pairs of electrons for coordination to the metal atoms, whereas a tertiary phosphine ligand can use only one lone pair of electrons for bridging coordination.
| Original language | English |
|---|---|
| Pages (from-to) | 3111-3118 |
| Number of pages | 8 |
| Journal | Inorganic Chemistry |
| Volume | 42 |
| Issue number | 9 |
| DOIs | |
| State | Published - May 5 2003 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Inorganic Chemistry
Cite this
Dynamical intramolecular metal-to-metal ligand exchange of phosphine and thioether ligands in derivatives PtRu5(CO)16(μ6-C). / Adams, Richard D.; Captain, Burjor; Fu, Wei; Pellechia, Perry J.
In: Inorganic Chemistry, Vol. 42, No. 9, 05.05.2003, p. 3111-3118.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Dynamical intramolecular metal-to-metal ligand exchange of phosphine and thioether ligands in derivatives PtRu5(CO)16(μ6-C)
AU - Adams, Richard D.
AU - Captain, Burjor
AU - Fu, Wei
AU - Pellechia, Perry J.
PY - 2003/5/5
Y1 - 2003/5/5
N2 - The complexes PtRu5(CO)15(PMe2Ph)(μ6-C) (2), PtRu5(CO)14(PMe2Ph)2 (μ6-C) (3), PtRu5(CO)15(PMe3)(μ6-C) (4), PtRu5(CO)14(PMe3)2 (μ6-C) (5), and PtRu5(CO)15(Me2S)(μ6-C) (6) were obtained from the reactions of PtRu5(CO)16(μ6-C) (1) with the appropriate ligand. As determined by NMR spectroscopy, all the new complexes exist in solution as a mixture of isomers. Compounds 2, 3, and 6 were characterized crystallographically. In all three compounds, the six metal atoms are arranged in an octahedral geometry, with a carbido carbon atom in the center. The PMe2Ph and Me2S ligands are coordinated to the Pt atom in 2 and 6, respectively. In 3, the two PMe2Ph ligands are coordinated to Ru atoms. In solution, all the new compounds undergo dynamical intramolecular isomerization by shifting the PMe2Ph or Me2S ligand back and forth between the Pt and Ru atoms. For compound 2, ΔH‡ = 15.1(3) kcal/mol, ΔS‡ = -7.7(9) cal/(mol·K), and ΔG298 = 17.4(6) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 4, ΔH‡ = 14.0(1) kcal/mol, ΔS‡ = -10.7(4) cal/(mol·K), and ΔG298 = 17.2(2) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 6, ΔH‡ = 18(1) kcal/mol, ΔS‡ = 21(5) cal/(mol·K) and ΔG298 = 12(2) kcal/mol. The shifts of the Me2S ligand in 6 are significantly more facile than the shifts for the phosphine ligand in compounds 2-5. This is attributed to a more stable ligand-bridged intermediate for the isomerizations of 6 than that for compounds 2-5. The intermediate for the isomerization of 6 involves a bridging Me2S ligand that can use two lone pairs of electrons for coordination to the metal atoms, whereas a tertiary phosphine ligand can use only one lone pair of electrons for bridging coordination.
AB - The complexes PtRu5(CO)15(PMe2Ph)(μ6-C) (2), PtRu5(CO)14(PMe2Ph)2 (μ6-C) (3), PtRu5(CO)15(PMe3)(μ6-C) (4), PtRu5(CO)14(PMe3)2 (μ6-C) (5), and PtRu5(CO)15(Me2S)(μ6-C) (6) were obtained from the reactions of PtRu5(CO)16(μ6-C) (1) with the appropriate ligand. As determined by NMR spectroscopy, all the new complexes exist in solution as a mixture of isomers. Compounds 2, 3, and 6 were characterized crystallographically. In all three compounds, the six metal atoms are arranged in an octahedral geometry, with a carbido carbon atom in the center. The PMe2Ph and Me2S ligands are coordinated to the Pt atom in 2 and 6, respectively. In 3, the two PMe2Ph ligands are coordinated to Ru atoms. In solution, all the new compounds undergo dynamical intramolecular isomerization by shifting the PMe2Ph or Me2S ligand back and forth between the Pt and Ru atoms. For compound 2, ΔH‡ = 15.1(3) kcal/mol, ΔS‡ = -7.7(9) cal/(mol·K), and ΔG298 = 17.4(6) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 4, ΔH‡ = 14.0(1) kcal/mol, ΔS‡ = -10.7(4) cal/(mol·K), and ΔG298 = 17.2(2) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 6, ΔH‡ = 18(1) kcal/mol, ΔS‡ = 21(5) cal/(mol·K) and ΔG298 = 12(2) kcal/mol. The shifts of the Me2S ligand in 6 are significantly more facile than the shifts for the phosphine ligand in compounds 2-5. This is attributed to a more stable ligand-bridged intermediate for the isomerizations of 6 than that for compounds 2-5. The intermediate for the isomerization of 6 involves a bridging Me2S ligand that can use two lone pairs of electrons for coordination to the metal atoms, whereas a tertiary phosphine ligand can use only one lone pair of electrons for bridging coordination.
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UR - http://www.scopus.com/inward/citedby.url?scp=0037998317&partnerID=8YFLogxK
U2 - 10.1021/ic0207000
DO - 10.1021/ic0207000
M3 - Article
C2 - 12716209
AN - SCOPUS:0037998317
VL - 42
SP - 3111
EP - 3118
JO - Inorganic Chemistry
JF - Inorganic Chemistry
SN - 0020-1669
IS - 9
ER -